After resist coating, exposure, and development, evaluation of the process is carried out by measuring a pattern width and the like using a CD-SEM (Critical Dimension-Scanning Electron Microscope). More specifically, a semiconductor inspection device such as the CD-SEM is used to determine whether a pattern on a sample such as a semiconductor wafer is correctly formed. In recent years, as finer patterns have been formed on samples such as semiconductor wafers, even very small adhering foreign matter cannot be overlooked.
The user checks for foreign matter day by day and starts steps for process evaluation if the number of foreign matter particles adhering to a wafer is less than a prescribed number. A dummy wafer is used to check for adhering foreign matter (Patent Literature 1). If however the prescribed number is exceeded, the use of the device is prohibited and a service engineer is called. The service engineer examines for a source and a cause of foreign matter emission, specifies a dust emission portion, and then carries out cleaning or replaces parts. Then, the device is operated for a predetermined period and the user gets back the device once it is confirmed that no more foreign matter is emitted.